A radioactive glucose tracer is used in a PET scan. More active brain tissue takes up more of the tracer.
The table shows results for one person.
Table
| Region | Tracer uptake at rest / arbitrary units | Tracer uptake during a task / arbitrary units |
|---|---|---|
| P | 20 | 50 |
| Q | 40 | 60 |
| R | 30 | 30 |
Which region has the greatest percentage increase in tracer uptake?
P, with an increase of 150%150\%150%
Q, with an increase of 150%150\%150%
Q, with an increase of 50%50\%50%
P, with an increase of 250%250\%250%
43 exam-style questions on Edexcel GCSE Biology 2.3 The nervous system and brain, covering 2.3.1 Structures and functions of the brain, 2.3.2 Imaging brain function with scanning, 2.3.3 Limitations in treating nervous system damage, 2.3.4 Neurones and impulse transmission, and 2.3.5 Structure and function of a reflex arc. Each one has a worked solution and a mark scheme showing where the marks go.